Julia was born in the later years of the reign of her adoptive great-grandfather, Emperor Augustus, and was the daughter of Drusus Julius Caesar (a grandson of Augustus wife' Livia Drusilla through her son Tiberius) and Livilla (a granddaughter of Livia Drusilla through her son Nero Claudius Drusus, and a granddaughter of Mark Antony through his daughter Antonia Minor).

The marriage appears to have been an unhappy one, and fell victim to the machinations of the notorious palace guardsman Sejanus, who exploited his intimacy with Julia's mother Livilla to scheme against Germanicus’ family.

Despite that Blandus had been consul suffect in 18, the match was considered a disaster; Tacitus includes the event in a list of "the many sorrows which saddened Rome", which otherwise consisted of deaths of different influential people.

[8] Around 43, an agent of the Roman Emperor Claudius' wife, Empress Valeria Messalina, had falsely charged Julia with incest and immorality.

It unhistorically has her mother attempting to poison her to prevent Sejanus from marrying her, but it is not explicit about whether she died as a result, so glossing over her fate under Claudius.